Five Excellent Reports on Kauai Pesticide Issues

Later this week a Joint Fact Finding Study Group from Kauai will release their report on pesticide use by large agricultural operations (seed corn and coffee), including any impacts to environmental and human health from such usage. If justified by evidence, they will also make recommendations.

The study group was created after passage of Bill 2491 and Ordinance 960, which would have put additional restrictions on pesticide use and the farming of genetically modified crops on Kauai. The ordinance was challenged in federal court, and was struck down in August 2014.

From the voluminous public testimony and articles in local media, the justification for the initial bill appeared to be mainly over concerns that pesticides were being applied in a manner dangerous to the health of communities near the large farms, that pesticides had caused children to become sick at school, the pesticides used by large farms were unacceptably hazardous and used at excessive rates, and that insufficient regulation by state and federal authorities required additional measures by the county government.

It appears that these concerns will be repeatedin the JFF report without the supporting evidence that pesticides are responsible for the alleged harms. Hopefully the final report, to be issued after public input on the draft, will also include and highlight the readily available studies which do not implicate pesticides. Concerns of the public are important and are not to be dismissed lightly, as we all want to be safe and enjoy a healthy environment and want to be assured that existing agricultural practices are compatible with these expectations.

We should appreciate that several state agencies have responded accordingly and taken this matter seriously, and what they have already found is reassuring as well as educational. Five excellent reports addressing the range of concerns are readily available, and very condensed summaries with excerpts from them are provided below.

This ambient air study was conducted in response to community concerns about occurrences at Kauai’s Waimea Canyon Middle School during which time some students and staff exhibited symptoms such as throat irritation, tearing, and dizziness. The Hawaii Department of Agriculture conducted regulatory compliance investigations, including the collection of environmental samples from the school and surrounding areas, of the odor and health complaints from the school and determined that there was no evidence to indicate that pesticides had been used improperly. At the time of these occurrences, stinkweed was growing in the fields near the school and was considered by some county emergency response officials to be the potential cause of the students’ symptoms.

Studies were conducted to determine (1) potential pesticide exposure and (2) if a locally common plant, stinkweed (Cleome gynandra), is producing odorous chemicals that may affect Waimea Canyon Middle School students and staff.

Two types of air sampling were then conducted on Kauai. For over a year, passive air sampling was used to identify chemicals in ambient air around the school and at other locations on Kauai for comparison. High volume sampling was conducted at Waimea Canyon Middle School and Hanalei Elementary School to detect chemicals in the ambient air and to determine the quantity of those chemicals.

Approximately half of the 29 chemicals produced by stinkweed were detected both in indoor and outdoor air samples collected from the passive and high volume air samplers positioned at Waimea Canyon Middle School and other Kauai schools. Five pesticides were detected in the indoor and outdoor passive air samples and the high volume outdoor air samples collected at Waimea Canyon Middle School.

Two of the five pesticides, dichlorodiphenyltrichloroethanes (DDTs) and benzene hexachlorides (BHCs), were widely used historically for mosquito and other insect control and are no longer in use.

The method of chemical detection used in the study, gas chromatography-coupled mass spectrometry, is highly sensitive and can detect very low concentrations of chemicals. Harmful effects are dependent upon both the toxicity of the chemical and the amount of exposure to the chemical. Concentrations of chlorpyrifos, metalochlor, and MITC in ambient air at the study sites on Kauai were approximately 24-, 650-, and 220-fold below the California screening levels. Chemical levels found in the air in each of the sampling sites on Kauai were all well below health concern levels.

People have raised concerns on Kauai about the health impact of pesticides used by agricultural chemical companies. In response to inquiries from community members on Kauai, the Hawaii Tumor Registry (HTR) evaluated the incidence of cancer on Kauai compared to the entire state of Hawaii. The evaluation found that there is not a higher incidence of cancer on Kauai compared to the rest of the state; except for melanoma.

This fact sheet addresses some key issues in evaluating cancer in communities, including pesticides and cancer, cancer facts, causes of cancer, cancers due to hazardous chemical substances, the rarity of cancer clusters, and US experience in cancer cluster investigations – only two possible cases out of thousands of investigations were able to show a statistically significant increase of cancer linked to an environmental chemical cause.

This report has been prepared in response to numerous community inquiries received by the Hawai‘i State Department of Health and the University of Hawai‘i Cancer Center, Hawai‘i Tumor Registry (HTR) regarding suspected elevated rates of cancer among residents of Kaua‘i. In the U.S., the overall incidence of cancer declined over the last decade. These national trends have also been observed in Hawai‘i. A specific cause for concern for a community would be to find substantially elevated risk beyond the trends exhibited in the state and country.

In general, cancer incidence on Kaua‘i was similar to or lower than that of the entire state of Hawai‘i. Overall cancer incidence rates (all cancers combined) were significantly lower on Kaua‘i compared to the entire state of Hawai‘i for both time periods (2000-2004 and 2005-2009).

We conclude that that there is no evidence of higher incidence of cancer on the island of Kaua‘i overall or for specific geographic regions of the island, as compared to the state of Hawai‘i. Melanoma was the exception whereby there is evidence of higher incidence on the island of Kaua‘i for the period 2000-2004. The primary risk factor for melanoma is exposure to ultraviolet radiation. It should be noted that in the state of Hawai‘i, individuals of Caucasian ancestry have the highest incidence of melanoma compared to other ethnic groups.

For the twenty year period between 1986 and 2005, the average annual proportion of births with birth defects is 4.4% (see below). Although the overall trend shows a reduction in birth defects, it is not statistically significant. Coincidentally, this period of no change spans the decade before and the first decade after GM crops were commercialized in 1996.

The birth defect rates for Hawaii County and Maui County were similar and significantly lower compared to the rates for the City and County of Honolulu and Kauai (see below).

This report also cautions about the problem of small numbers in data interpretation: Rates and proportions based on fewer than 20 reported cases are not considered reliable due to small numbers and potential fluctuation from year to year. In particular, birth defect conditions with less than five reported cases need to be interpreted with caution.

This Study was prepared in response to section 3 of Act 105, Session Laws of Hawaii 2013 that directed the Legislative Reference Bureau to determine whether other states impose reporting requirements on pesticides that do not fall within the definition of a “restricted use pesticide,” as that term is defined under the Hawaii Pesticides Law.

It appears that the majority of states do not impose any reporting requirements on pesticides that do not fall within the definition of a restricted use pesticide. States with reporting requirements on the sale of general use pesticides (GUPs) include Idaho, Iowa and Maine; states with reporting requirement on the use of GUPs are Massachusetts and Oregon: and states with reporting requirements on both the sale and use of GUPs are California and New York.

There appears to be a great deal of variation between the extent to which these reporting requirements are applied and enforced from one state to another. It should be noted that, in addition to the fact that each of these states employs a different approach with regard to reporting requirements, the Bureau could not find any sort of comprehensive evaluation on the effectiveness of any of the various reporting programs. Therefore, it is difficult to determine whether and to what extent any of them have been successful in achieving the objectives for which each program was established.

The Bureau was unable to secure detailed information regarding the costs incurred by these states in establishing and maintaining their various reporting programs. The Bureau offers no conclusions regarding the budgetary requirements of such programs, other than to note that, as discussed previously, both Oregon and New York appear to have encountered difficulties resulting from the cost of maintaining their reporting programs.

* * *

These five reports provide reasoned answers to many of the questions and concerns of the public and policy makers about pesticides on Kauai. However, science is a continual process where new, credible evidence that adds to existing knowledge is how progress is made. Will the joint study group provide new, credible evidence that changes what we already know from these other studies? Let’s see.